Cell Bio Final Ho15

Front 1

size of Microfilaments

Back 1

7-9 nm

Front 2

Microfilaments are made of

Back 2

2 actin strands

Front 3

Inermediate Filaments are how big?

Back 3

10 nm

made of including keratin
& various proteins

Front 4

Microtubules are how big?

Back 4

largest --> 25nm

Front 5

Microtubules are made of

Back 5

alpha & beta tubulin

may be hollow inside

Front 6

what holds nucelus in place

Back 6

Intermediate filaments

Front 7

Microfilaments are mainly associated w/

Back 7

Plasma Membrane

Front 8

which end of a Microfilament is growing?

Back 8

+ (barbed) end

ATP is NOT exposed

Front 9

Tubulins bind what?

Back 9

GTP

Front 10

actins bind what

Back 10

ATP

Front 11

Motor protein for actin is

Back 11

Myosin

Front 12

Myosin & Actin

Pointed End

Barbed End

Back 12

Pointed End ----

Barbed End ++++

Front 13

Actin filament treadmilling is accelerated by

Back 13

profilin and cofilin

Front 14

Profilin

Back 14

binds to monomeric actin

lowers Cc

slows microfilament polymerization

Front 15

Cofilin

Back 15

enhances rate of loss on - end

binds actin-ADP

Front 16

why does + & - ends of microfilament have different association rate?

Back 16

older end (-) w/ Exposed ATP is more likely to be hydrolzyed --> conformaitonal change

- has higher Cc

treadmilling can be used for work

Front 17

Thymosin-Beta4

Back 17

binds G-actin --> not avalible

provides reserve actin when needed

Front 18

CapZ

Back 18

binds microfilament on + end

Front 19

Troponmodulin

Back 19

binds microfilament on - end

stabilizes

Front 20

Formins

Back 20

starts actin nucleation

starts microfilament

Front 21

Arp 2/3 complex

Back 21

makes branched microfilaments at 70 degree angle

Front 22

Listeria & actin

Back 22

uses Arp2/3 & formins &. . .

intracellular pathogen that can pass from cell to cell without lysis
food poisoning
not that dangerous
can cause abortion
Listeria can “ride” actin bundles out of an infected cell

Front 23

Toxins that prevent polymerization

Back 23

Cytochalasin B binds to + end, preventing polymerixation

Latruculin binds to G actin preventin polymeriztation

Front 24

Toxins that prevent depolymerization

Back 24

Phalloidin binds to F actin, preventing depolymeriation

Jasplakolinode: dimerizes G actin, lowering Cc, perventing polimerization

Front 25

which end of microfilaments points toward membrane?

Back 25

+ end or Lateral

listeria grows microfilaments out of cells

Front 26

What hand over hand down an actin filament

Back 26

Myosin V

Front 27

spherocytic anemias

Back 27

genetic disease liniked to microfiliaments

RBC cytoskeleton

Front 28

what part of myosin attaches to actin?

Back 28

head

Front 29

what part of myosin can carry cargo?

Back 29

neck

Front 30

Myosin with

Large steps

small steps

Back 30

Large= Myosin V hand over hand 72nm step-moves only 36

small=myosin II 5-15

Front 31

skeletal muscle

Back 31

myosin II

Front 32

myosin move toward ___ end

Back 32

+ end of microfilaments

Front 33

Nebulin

Back 33

associates & stabilizes actin thin filaments

Front 34

Titin

Back 34

associates with Myosin thick filaments

Front 35

these types of mysoin move vessicals

Back 35

Myosin I

Myosin V

Front 36

No ATP causes Myosin to

Back 36

lock on actin

riggamortus

Front 37

binding ATP causes Myosin to

Back 37

Myosin head releases Actin

Front 38

ATP hydrolysis causes myosin to

Back 38

be in the cocked position

ready to fire/drive

Front 39

at low Ca++ this blocks interaction btw Myosin & thin filaments

Back 39

Tropomyosin

Front 40

this binds Ca++

Back 40

troponin complex associated w/ tropomyosin binds Ca++ & moves the tropomyosin to uncover the myosin binding sites on actin allowing contraction

Front 41

contractil bundles are regulated by ___

Back 41

thick filament

Front 42

myosin light chain is P-lated by?

Back 42

Myosin Light Chain Kinase

Front 43

functional contractil unit

Back 43

sacromere